Romina Camilli1, Maria Fenicia Vescio1, Maria Giufrè1, Laura Daprai2, Maria Laura Garlaschi2, Marina Cerquetti1, Annalisa Pantosti3. 1. Department of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanità, Rome, Italy. 2. Unit of Microbiology, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milan, Italy. 3. Department of Infectious, Parasitic and Immune-mediated Diseases, Istituto Superiore di Sanità, Rome, Italy. Electronic address: annalisa.pantosti@iss.it.
Abstract
BACKGROUND: The pneumococcal population changes observed after the implementation of children immunization with pneumococcal conjugative vaccines (PCV) might have affected the composition of the microbial flora inhabiting the same ecological niche of Streptococcus pneumoniae. The aim of this study was to investigate the effect of PCV immunization, (PCV7 or PCV13), on S. pneumoniae and Haemophilus influenzae colonization in young children in Italy. METHODS: Nasopharyngeal swabs were obtained from 301 children under 6 years of age (vaccinated or unvaccinated with PCV) during the period January-April 2012. Presence of S. pneumoniae and H. influenzae was investigated using conventional cultural methods. S. pneumoniae isolates were serotyped by the Quellung reaction; capsular type of H. influenzae isolates was determined by PCR. The pattern of associations between the two species and potential risk factors were investigated by a Structural Equation Modelling (SEM) analysis. RESULTS: The prevalence of carriage was 31.56% and 43.18% for S. pneumoniae and H. influenzae, respectively. The majority of S. pneumoniae isolates belonged to non vaccine serotypes (non PCV13-types 81.1%) while H. influenzae isolates were all non-typeable. SEM analysis revealed a synergistic association between S. pneumoniae and H. influenzae colonization (rho: 0.27; 95%CI: 0.09-0.46; p=0.004). In addition, children vaccinated with PCV, either with PCV7 (coef 0.43; 95%CI: 0.07-0.79; p=0.021) or with PCV13 (coef: 0.45; 95%CI: 0.08-0.82; p=0.018), were more likely to be colonized by H. influenzae. CONCLUSIONS: Pneumococcal vaccination increased H. influenzae nasopharyngeal carriage in children. This result highlights that an indirect effect of PCV vaccination can be perturbation of the nasopharyngeal flora. In the era of higher-valent pneumococcal vaccines, surveillance of carriage is crucial to monitor alterations in the bacterial ecosystem, thus preventing possible clinical problems.
BACKGROUND: The pneumococcal population changes observed after the implementation of children immunization with pneumococcal conjugative vaccines (PCV) might have affected the composition of the microbial flora inhabiting the same ecological niche of Streptococcus pneumoniae. The aim of this study was to investigate the effect of PCV immunization, (PCV7 or PCV13), on S. pneumoniae and Haemophilus influenzae colonization in young children in Italy. METHODS: Nasopharyngeal swabs were obtained from 301 children under 6 years of age (vaccinated or unvaccinated with PCV) during the period January-April 2012. Presence of S. pneumoniae and H. influenzae was investigated using conventional cultural methods. S. pneumoniae isolates were serotyped by the Quellung reaction; capsular type of H. influenzae isolates was determined by PCR. The pattern of associations between the two species and potential risk factors were investigated by a Structural Equation Modelling (SEM) analysis. RESULTS: The prevalence of carriage was 31.56% and 43.18% for S. pneumoniae and H. influenzae, respectively. The majority of S. pneumoniae isolates belonged to non vaccine serotypes (non PCV13-types 81.1%) while H. influenzae isolates were all non-typeable. SEM analysis revealed a synergistic association between S. pneumoniae and H. influenzae colonization (rho: 0.27; 95%CI: 0.09-0.46; p=0.004). In addition, children vaccinated with PCV, either with PCV7 (coef 0.43; 95%CI: 0.07-0.79; p=0.021) or with PCV13 (coef: 0.45; 95%CI: 0.08-0.82; p=0.018), were more likely to be colonized by H. influenzae. CONCLUSIONS:Pneumococcal vaccination increased H. influenzae nasopharyngeal carriage in children. This result highlights that an indirect effect of PCV vaccination can be perturbation of the nasopharyngeal flora. In the era of higher-valent pneumococcal vaccines, surveillance of carriage is crucial to monitor alterations in the bacterial ecosystem, thus preventing possible clinical problems.
Authors: Eszter Kovács; Judit Sahin-Tóth; Adrienn Tóthpál; Mark van der Linden; Tamás Tirczka; Orsolya Dobay Journal: PLoS One Date: 2020-02-07 Impact factor: 3.240
Authors: Irene Rivero-Calle; Jose Gómez-Rial; Louis Bont; Bradford D Gessner; Melvin Kohn; Ron Dagan; Daniel C Payne; Laia Bruni; Andrew J Pollard; Adolfo García-Sastre; Denise L Faustman; Albert Osterhaus; Robb Butler; Francisco Giménez Sánchez; Francisco Álvarez; Myrsini Kaforou; Xabier Bello; Federico Martinón-Torres Journal: Hum Vaccin Immunother Date: 2020-08-05 Impact factor: 3.452
Authors: Michael T Bailey; Christian L Lauber; Laura A Novotny; Steven D Goodman; Lauren O Bakaletz Journal: mSphere Date: 2020-04-15 Impact factor: 4.389